| 摘要 |
PURPOSE:To perform secure inspection by allowing a gas circuit to change above and below an operating flow rate, i.e. into two states and providing a circuit which cuts off a flow at the upstream side of the overflow preventing valve during said changing period. CONSTITUTION:The 1st flow rate setting device 24 and the 2nd flow rate setting device 25 which are set above and below the operating flow rate of the overflow preventing valve 10 are provided at the upstream and downstream sides of the hole part 21 of an overflow preventing valve insertion part 21. Then, only the 1st solenoid valve 22 is opened and the valve 10 inserted into the hole part 21 is operated forcibly. Then, the valve 22 is reset into the closed state, a discharge valve 27 is opened, and then only the 2nd solenoid valve 23 is opened. Data on a series of those operations are inputted to the 1st, the 2nd, and the 3rd driving circuits 29a, 29b, and 20c corresponding to the respective solenoid valves on the basis of a signal output predetermined by a control valve. The output of a pressure switch 26 is inputted to the 1st pilot lamp 20a and also inputted to the 2nd pilot lamp 20b through an AND circuit 2 together with the output of the circuit 29b for the valve 23. Therefore, the operation of the valve 10 is confirmed from the on state of the lamp 20a and a defect in resetting is confirmed from the on state of the lamp 20b. |
